Dont Know. Neighbor took pic and killed snake in the same pile of branches I was cutting up last night! Im now 100 Miles away and he has lousy cell svc
I did a google and there are many close ones but Fox and Rat snake stood out, but also prairie rattlesnake. Just asked WWW blind question and he said looks like prairie rattlers like he saw in CA as a kid. Glad you did not encounter it!
Most poisonous snakes are very thick bodied and have blocky heads. Pretty comfortable saying it's a constricted, it's not a copperhead or rattle snake.
That also could be a milk snake. If so, they make you think they are rattlers when they coil and start wiggling their tails. They can be aggressive too. We see them quite often here.